In a container for a flow of pulp it is often essential that the residence time of the pulp in the container be substantially the same for all portions of the pulp flowing through the container. This particularly applies to treatment of the pulp by an agent, for example in the bleaching of the pulp. It is, thus, essential to avoid channelization in the container. During the treatment of the pulp with an agent, which is supplied prior to the supply of the pulp to the container, it is also important that the agent be distributed uniformly in the pulp at the inlet to the container, in order to thereby achieve homogenous treatment. It has thus been found that the way in which the pulp is supplied to the container is of decisive importance for the solution of the aforesaid problems.
During the supply of pulp, different types of distributors are used. For example, these include mechanical distributors with an inlet housing and an axial rotor, the shaft of which is supported in bearings and sealed by a packing box. A gear and a motor are thus required for driving the rotor.
Mechanical distributors are also used, in which a rotor is formed with two or more outlet channels.
These mechanical distributors generally require a complicated design, because they comprise a rotor with an accessory drive, bearings, and a sealing arrangement. These distributors are also not adapted to varying pulp flows and production levels.
According to a somewhat simplified construction, a distributor is used which comprises a pump-like housing outside the container bottom, where at least four outlets are arranged symmetrically about the circumference of the container. Such a device requires a control valve in each outlet and separate pipe lines for connection to the container. This device is also very complicated, while its distribution effect is rather limited, and its flow direction is wrong.
In addition to the mechanical distributors, there also exist static distributors with conical surfaces for dispersing the pulp in the container. These distributors cannot be controlled, and the distribution achieved is often insufficient.